The NIH and other federal agencies see provider-based research networks (PBRNs) as a promising model for disseminating and implementing evidence-based clinical services in community-based practice settings. PBRNs are collaborative partnerships between community-based providers and academic institutions to conduct clinical research on an ongoing basis. As an indicator of its commitment to PBRNs, the NIH is investigating the feasibility of training 50,000 community-based health-care practitioners to participate in clinical research and integrate new research findings into routine health care delivery. Yet, reports indicate that PBRNs are challenging to implement and sustain. Further, the extent to which PBRNs actually promote the use of evidence-based clinical services in community-based practice settings remains largely unknown. This project will examine the implementation, impact, sustainability, and business case of the NCI's Community Clinical Oncology Program (CCOP), a federally funded national PBRN that the NIH sees as a model for PBRNs in other disease areas. Specifically, the project will (1) investigate the implementation of the CCOP in community-based practice settings through in-depth case studies of three newly funded CCOP organizations and a survey of all 50 CCOP organizations; (2) examine the impact of the CCOP on clinical practice through longitudinal analysis of adoption rates of evidence-based cancer therapies by CCOP- affiliated and non-CCOP-affiliated providers using SEER-Medicare data; (3) assess the factors affecting sustainability of the CCOP in community-based practice settings through a longitudinal analysis of all CCOP organizations active from 1991 through 2003; and (4) investigate the business case for CCOP participation by providers through analysis of financial and statistical data and in-depth case studies. The project will provide the NIH with much-needed information about what it takes to implement and sustain PBRNs and what it can expect from PBRNs as a model for disseminating and implementing evidence-based clinical services in community-based practice settings.